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      <a id="metro"></a>
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        <h2>
          <span class="refentrytitle">metro</span>
        </h2>
        <p>metro — 
     Trigger Metronome
          </p>
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      <div class="refsect1">
        <a id="idp123426144"></a>
        <h2>Description</h2>
        <p>
	Generate a metronomic signal to be used in any circumstance an isochronous trigger is needed.
    </p>
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      <div class="refsect1">
        <a id="idp123490112"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">ktrig  <span class="command"><strong>metro</strong></span>  kfreq [, initphase]</pre>
      </div>
      <div class="refsect1">
        <a id="idp123492192"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>initphase</em></span>  - initial phase value (in the 0 to 1 range)
    </p>
      </div>
      <div class="refsect1">
        <a id="idp123493936"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>ktrig</em></span> - output trigger signal
    </p>
        <p>
      <span class="emphasis"><em>kfreq</em></span> - frequency of trigger bangs in cps
    </p>
        <p>
     <span class="emphasis"><em>metro</em></span> is a simple opcode that outputs a sequence of isochronous bangs (that is 1 values) each 1/kfreq seconds. Trigger signals can be used in any circumstance, mainly to temporize realtime algorithmic compositional structures.
     </p>
        <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
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              <th align="left">Note</th>
            </tr>
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              <td align="left" valign="top">
                <p>
        <span class="emphasis"><em>metro</em></span> will produce a trigger signal of 1 when its phase is exactly 0 or 1. If you want to skip the initial trigger, use a very small value like 0.00000001.
     </p>
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      <div class="refsect1">
        <a id="idp123499392"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the metro opcode. It uses the file <a class="ulink" href="examples/metro.csd" target="_top"><em class="citetitle">metro.csd</em></a>
      </p>
        <div class="example">
          <a id="idp123501136"></a>
          <p class="title">
            <strong>Example 485. Example of the metro opcode.</strong>
          </p>
          <div class="example-contents">
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
-odac -B441 -b441
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span>     <span class="op">=</span>        44100
<span class="ohdr">kr</span>     <span class="op">=</span>        100
<span class="ohdr">ksmps</span>  <span class="op">=</span>        441
<span class="ohdr">nchnls</span> <span class="op">=</span>        2

       <span class="oblock">instr</span>    1
ktrig <span class="opc">metro</span> 0.2
<span class="opc">printk2</span> ktrig
	<span class="oblock">endin</span>

<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="stamnt">i</span> 1 0 20


<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <p><br class="example-break" />
            Here is another example of the metro opcode. It uses the file <a class="ulink" href="examples/metro-2.csd" target="_top"><em class="citetitle">metro-2.csd</em></a>
      </p>
        <div class="example">
          <a id="idp123503648"></a>
          <p class="title">
            <strong>Example 486. Another example of the metro opcode.</strong>
          </p>
          <div class="example-contents">
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac   <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if realtime audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o metro-2.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="ohdr">0dbfs</span>  <span class="op">=</span> 1

<span class="oblock">instr</span> 1

kpch    <span class="opc">random</span>   1,20		<span class="comment">;produce values at k-rate</span>
ktrig   <span class="opc">metro</span>    10		<span class="comment">;trigger 10 times per second</span>
kval	<span class="opc">samphold</span> kpch, ktrig 	<span class="comment">;change value whenever ktrig = 1 </span>
asig	<span class="opc">buzz</span>	 1, 220, kval, 1<span class="comment">;harmonics</span>
        <span class="opc">outs</span>     asig, asig

<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="stamnt">f</span> 1 0 4096 10 1	<span class="comment">; sine</span>

<span class="stamnt">i</span> 1 0 10
<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
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        <p><br class="example-break" />
    </p>
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      <div class="refsect1">
        <a id="idp123505568"></a>
        <h2>See Also</h2>
        <p> More information on this opcode in the Floss Manuals: <a class="ulink" href="http://en.flossmanuals.net/csound/ch018_c-control-structures/" target="_top"><em class="citetitle">http://en.flossmanuals.net/csound/ch018_c-control-structures/</em></a></p>
      </div>
      <div class="refsect1">
        <a id="idp123507632"></a>
        <h2>Credits</h2>
        <p>Written by Gabriel Maldonado.</p>
        <p>First Example written by Andrés Cabrera.</p>
        <p>New in Csound 5 (Previously available only on CsoundAV)</p>
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